1. Field of the Invention
The present invention relates generally to a vending machine, and more particularly to a cup transfer device for a vending machine that transfers a supplied cup from a cup supply device between a cup supply unit and a low material discharging hole.
2. Description of the Related Art
A conventional cup transfer device 10 of a vending machine is shown in FIG. 1. The cup transfer device 10 of the vending machine shown in FIG. 1 is an undisclosed prior art device of the assignee of the present invention, thus, it cannot be used as a ground for rejecting the present invention.
Referring to FIG. 1, the conventional cup transfer device 10 of the vending machine comprises a cup holder 110, a driving means 120, and a position control means 130. The cup holder 110 comprises a holder body 111 and a cup hold unit 112 for embracing a cup.
The driving means 120 includes a motor 121 (shown in phantom) and a gear box 122 (shown in phantom). Rotational force of the motor 121 is amplified by the gear box 122, and provides rotational energy to a rotary shaft 123. Accordingly, the cup holder 110, secured to the rotary shaft 123, also rotates.
The position control means 130 comprises a sensing disk 131 and a pair of sensors 132 and 133. The sensing disk 131 is secured to the cup holder 110 by an appropriate means, such as the pins shown, and the pair of sensors 132 and 133 are secured to a base plate 101 by a bracket 134.
A plurality of sensing detents 132a, 133a and 133b are formed along an outer circumference 135 of the sensing disk 131. Alternatively, the sensing disk 131 can be formed integrally with the cup holder 110. Original point and stop positions of the cup holder 110 are controlled in accordance with a reciprocal movement of the pair of sensors 132 and 133 in the sensing detents 132a, 133a and 133b. In other words, the original point of the cup holder 110 is controlled by the relative movement of the sensor 132 in the sensing detent 132a, and the stop position of the cup holder 110 is controlled by the relative movement of the sensor 133 in the sensing detents 133a and 133b. 
For the conventional cup transfer device 10 of the vending machine with the above described construction, if the stop position of the cup holder 110 is sensed by the sensor 133 and the sensing detents 133a and 133b, the stop position of the cup holder 110 is controlled by stopping the operational rotation of the motor 121.
However, according to the position control method of the cup holder 110 as described above, the cup holder 110 sometimes cannot stop at the appropriate place due to inertial forces of a rotary body or the change of viscosity of grease inside of the gear box 122 caused by a change in the weather.
In the above case, supplying of the cup and discharging of the ice cream cannot be performed actively. Accordingly, the vending machine might be polluted because the ice cream is discharged to the wrong place and the useful credibility of the vending machine can be damaged.
The present invention has been made to overcome the above-mentioned problems of the related art. Accordingly, it is an object of the present invention to provide a cup transfer device of a vending machine capable of accurately controlling a stop position of a cup holder.
The above object of the present invention is accomplished by providing a cup transfer device of a vending machine, comprising a cup holder; means for driving the cup holder; means for controlling a position of the cup holder; and means for adjusting a position of the cup holder.
The driving means includes a motor and gear box, the position control means is secured to the cup holder, and includes a sensing disk having a plurality of sensing detents formed at an outer circumference and a pair of sensors that reciprocate with the sensing detents. Moreover, in various preferred embodiments of the present invention, the position adjusting means can include position adjusting detents formed at an outer circumference of a sensing disk and a roller urged toward the outer circumference of the sensing disk by a resilient member, and also can include a position adjusting detent formed at an outer circumference of a sensing disk and a wedge member for selectively engaging with the position adjusting detent or can include a magnetic material attached at an outer circumference of a sensing disk and an electromagnet for selectively operating with the magnetic material.